1. Field of the Invention
The present invention relates to a returnable case capable of being assembled and disassembled in use for transportation of packaged freight.
2. Brief Description of the Prior Art
An example of a conventional returnable case which is disassembled as necessary comprises a skid as a bottom plate, support frames disposed on the front and rear edges of the skid, side frames disposed on the left and right edges of the skid, and a top frame connected to each of the side frames. Such a returnable case is normally assembled at a packaging site by securing all components to each other with bolts.
In conventional returnable cases, when loaded in a container or the like at returning time, each member of the case cannot be compactly enclosed, therefore making it difficult to place a number of cases without occupying a large space. Also, in conventional cases, nuts to be fastened to bolts were welded on each retaining portion. If the threads were erased, the case would become impossible to reassemble.
Some conventional returnable cases, in which wooden or steel materials were employed for the bottom, were not strong enough, and therefore not reused or required much labor for disassembly and reassembly. Another example of a case, which included a hinged connection between the frames and skid, had the further disadvantage of not being collapsible into a relatively narrow form for packing.